Effect of MgO Activity Index on Physicochemical, Electrical and Mechanical Properties of Carbonated MgO-admixed Silt

Guanghua Cai,Songyu Liu,Guangyin Du,Liang Wang 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.9

The natural soil will have a significant strength improvement when admixed with reactive magnesia (MgO) and subjected to CO2 carbonation, which has been identified as an innovative and environment-friendly technique in the domain of soil treatment. MgO activity has been revealed to have a significant influence on the treatment effectiveness during the carbonation process. With this in view, the effect of MgO activity index on physicochemical, electrical and strength properties of carbonated silt was investigated. Results show that the MgO activity index and initial water-MgO ratio play crucial roles in controlling the aforementioned properties. With the initial water-MgO ratio reducing or MgO activity index increasing, the mass increment ratio, growth rate of unit weight, pH, resistivity, strength and CO2 sequestration increase to different degrees, while the volume increment ratio, water content, specific gravity, porosity and saturation degree decrease. The unconfined compressive strength shows a better linear relation with resistivity, indicating the applicability of resistivity method in the strength evaluation of carbonated MgO-admixed soil. Moreover, the thermal and microstructural analyses have explained the changing mechanism of physicochemical, electrical and strength properties. Finally, the analysis of the CO2 sequestration indicates that the carbonated MgO-admixed silt could achieve a high carbonation degree when the initial water-MgO ratio is less than 2.0, showing the feasibility of MgO carbonation in the CO2 sequestration.

Grinding Experiment by Direct Position/Force Control with On-line Constraint Estimation

Guanghua Chen,Mamoru Minami,Geng Wang 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

Based on the analyses of the interaction between a manipulator’s hand and a working object, a model rep-resenting the constrained dynamics of the robot is first discussed. The constrained forces are expressed by analgebraic function of states, input generalized forces, and constraint condition, and then direct position/force controller with out force sensoris proposed based on the algebraic relation. To give the grinding system the ability to adapt to any object shape being changed by itself, we added new estimating function of time-varying constraint condition in realtime for the adaptive position/force control. Evaluations through simulations and real grinding experiments by fitting the changing constraint surface with spline functions, indicate that reliable position/force control and shape-grinding can beachieved by the proposed methodology.

Tensile Behavior of High-Strength Stainless Steel Wire Rope (HSSSWR)-Reinforced ECC

Xinling Wang,Guanghua Yang,Wenwen Qian,Ke Li,Juntao Zhu 한국콘크리트학회 2021 International Journal of Concrete Structures and M Vol.15 No.6

Engineered cementitious composites (ECC) show the distinguished characteristics of high post-cracking resistance and ductility. High-strength stainless steel wire rope (HSSSWR) has been successfully used for restoring or strengthening of existing structures. By combining the advantages of these two materials, a new composite system formed by embedding HSSSWR into ECC was proposed and expected to be a promising engineering material for repair or strengthening of structures. To investigate the tensile failure mechanism and mechanical properties of HSSSWR-reinforced ECC, an experimental study on 27 HSSSWR-reinforced ECC plates was conducted considering the effects of the reinforcement ratio of longitudinal HSSSWRs, formula of ECC and width of the plate. Test results revealed that HSSSWR-reinforced ECC exhibit superior post-cracking resistance, deformation capacity and crack-width control capacity. Increasing the reinforcement ratio of longitudinal HSSSWRs can effectively enhance the tensile strength, crack-width control capacity, deformation capacity and tensile toughness of HSSSWR-reinforced ECC. Adding thickener in ECC can significantly improve the crack-width control capacity and deformation capacity of HSSSWR-reinforced ECC due to enhancing uniform distribution of polyvinyl alcohol fibers, but would slightly reduce the cracking stress and maximum tensile stress by bringing small bubbles in the matrix. The tensile properties of HSSSWR-reinforced ECC plates are almost not affected by varying the plate width. Besides, a tensile constitutive model was developed for charactering the stress-strain relationship of HSSSWR-reinforced ECC in tension. Based on mechanical theories and failure characteristics of HSSSWR-reinforced ECC, the model parameters were determined, and calculation equations of cracking stress and tensile strength were proposed. The accuracy of the developed model and calculation equations was verified by test results.

The Fate of Soybean Photosynthetic Carbon Varies in Mollisols Differing in Organic Carbon

Jian Jin,Guanghua Wang,Judong Liu,Zhenhua Yu,Xiaobing Liu,Stephen J Herbert 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Regulating the magnetic anisotropy by Hf thickness and heat treatment in Pt/Co/Hf films

Li Minghua,Zhang Shijie,Wang Shuanghai,Li Yongzeng,Liu Lu,Chen Yu,Shi Hui,Yu Guanghua 한국물리학회 2022 Current Applied Physics Vol.34 No.-

Pt/Co/Hf multilayers were prepared by magnetron sputtering, and the magnetic anisotropy was effectively regulated by Hf thickness and heat treatment in Pt/Co/Hf films. The interface microstructures were characterized. The influence of the interface microstructure on magnetic properties was studied. The results show that the magnetic anisotropy in Pt/Co/Hf films is closely related to the interface microstructure, which is influenced by Hf thickness and the heat treatment temperature. Microstructure analysis shows that after the Pt(3)/Co(1.5)/Hf (1) film is heat-treated, the CoOx content increases, more CoPt(111) forms, the interface is smoother and sharper, and the roughness of the Co/Hf interface decreases. Several factors work together to cause the magnetic anisotropy of the sample to change from in-plane magnetic anisotropy (IMA)to perpendicular magnetic anisotropy (PMA).

Effect of Basicity and B2O3 on Viscosity, Melting and Crystallization Behaviors of Low Fluorine Mold Fluxes for Casting Medium Carbon Steels

Lejun Zhou,Wanlin Wang,Boxun Lu,Guanghua Wen,Jian Yang 대한금속·재료학회 2015 METALS AND MATERIALS International Vol.21 No.1

As potential substitutes for fluorides, the influences of basicity and B2O3 content on viscosity, melting andcrystallization behaviors of low fluorine mold fluxes for casting medium carbon steels were investigatedby using Brookfield viscometer and Single Hot Thermocouple Technique in this study. Results suggestedthat, the break temperature, crystallization temperature and critical cooling rate of low fluorine mold fluxeswere increased with the increase of basicity; while they were decreased with the further addition of B2O3. Meantime, the viscosity and melting temperature range were first attenuated, and then increased greatlywith the increase of basicity; however, they would tend to be reduced with the addition of B2O3 content. Also, it was found that the viscosity of mold flux is not only decided by the degree of polymerization ofsilicate structure, but also greatly affected by its crystallization behavior.

Enhanced construction of gene regulatory networks using hub gene information

Yu, Donghyeon,Lim, Johan,Wang, Xinlei,Liang, Faming,Xiao, Guanghua BioMed Central 2017 BMC bioinformatics Vol.18 No.1

<P><B>Background</B></P><P>Gene regulatory networks reveal how genes work together to carry out their biological functions. Reconstructions of gene networks from gene expression data greatly facilitate our understanding of underlying biological mechanisms and provide new opportunities for biomarker and drug discoveries. In gene networks, a gene that has many interactions with other genes is called a hub gene, which usually plays an essential role in gene regulation and biological processes. In this study, we developed a method for reconstructing gene networks using a partial correlation-based approach that incorporates prior information about hub genes. Through simulation studies and two real-data examples, we compare the performance in estimating the network structures between the existing methods and the proposed method.</P><P><B>Results</B></P><P>In simulation studies, we show that the proposed strategy reduces errors in estimating network structures compared to the existing methods. When applied to <I>Escherichia coli</I>, the regulation network constructed by our proposed ESPACE method is more consistent with current biological knowledge than the SPACE method. Furthermore, application of the proposed method in lung cancer has identified hub genes whose mRNA expression predicts cancer progress and patient response to treatment.</P><P><B>Conclusions</B></P><P>We have demonstrated that incorporating hub gene information in estimating network structures can improve the performance of the existing methods.</P>

Heterogeneous Fenton degradation of Orange II by immobilization of Fe3O4 nanoparticles onto Al-Fe pillared bentonite

Wenbing Li,Dong Wan,Guanghua Wang,Kun Chen,Qin Hu,Lulu Lu 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.5

A novel catalyst, Fe3O4 nanoparticle decorated Al-Fe pillared bentonite (Fe3O4/Al-Fe-P-B), was prepared by in situ precipitation oxidization method. The catalyst was characterized by SEM, XRD and Raman spectroscopy. The Fe3O4 nanoparticles mainly exist on the surface or enter into the pore of bentonite, with better dispersing and less coaggregation. The catalytic activity of Fe3O4/Al-Fe-P-B was investigated in the degradation of Orange II (OII) by heterogeneous Fenton-like process. The effects of initial concentration of hydrogen peroxide, catalyst loading, temperature and initial pH on the degradation of OII were investigated. The Fe3O4/Al-Fe-P-B showed higher degradation efficiency of OII than bare Fe3O4 or Al-Fe-P-B in the degradation experiment. The enhanced catalytic activity of Fe3O4/Al-Fe-P-B in heterogeneous Fenton system was due to the synergistic effect between Al-Fe-P-B and Fe3O4. The novel catalyst can achieve solid-liquid separation easily by sample magnetic separation and has a good reusability and stability.

Comparative analysis of bovine maternal corpus luteum microRNAs with aberrant and normal developed cloned fetus at late gestation

Xiaohu Su,Shenyuan Wang,Guangqi Gao,Xinyu Zho,Lidong Han,Guanghua Su,Jiaqi Zhang,Wanfu Bai,Xiuying Wang,Guangpeng Li,Li Zhang 한국유전학회 2020 Genes & Genomics Vol.42 No.3

Background The development efficiency of cloned cattle is extremely low (< 5%), most of them were aborted at late gestation. Based on our previous studies, some recipient cows with a cloned fetus would present as engorged uterine vessels and enlarged umbilical vessels randomly. Abortion involves both maternal and fetal factors. Objective Our aim was to explore this phenomenon by microRNAs expression profile analysis of maternal corpus luteum (CL), which was related to pregnancy maintenance. Methods The present study provided the comparison of maternal CL miRNAs expression of abnormally and normally developed cloned bovine fetus at late gestation (~ 210 days) using RNA-Seq technology. Results We selected two abnormally pregnant cows (abnormal group, AG) and three normally pregnant cows (normal group, NG) and acquired valid reads of 9317,261–12,327,185 (~ 84.53–91.28%) from five libraries. In total, we identified 981 conserved miRNAs and 223 novel miRNAs. 1052 miRNAs were co-expressed, 124 miRNAs were uniquely expressed in AG, and 93 miRNAs were uniquely expressed in the NG. Compared with NG, 11 were significantly overexpressed, and 22 were downregulated (p < 0.05) at AG among 1052 co-expressed miRNAs. The differentially expressed miRNAs-targeted genes were further analyzed by Gene Ontology and KEGG pathway analysis. Notably, the steroid biosynthesis pathway was a significantly enriched term (p < 0.01), which may affect the secretion of progesterone. Conclusion Our research suggested that abnormal miRNAs expression of bovine maternal CL may affect the pregnant status at late gestation.

A community computational challenge to predict the activity of pairs of compounds

Bansal, Mukesh,Yang, Jichen,Karan, Charles,Menden, Michael P,Costello, James C,Tang, Hao,Xiao, Guanghua,Li, Yajuan,Allen, Jeffrey,Zhong, Rui,Chen, Beibei,Kim, Minsoo,Wang, Tao,Heiser, Laura M,Realubit Nature Publishing Group, a division of Macmillan P 2014 Nature biotechnology Vol.32 No.12

Recent therapeutic successes have renewed interest in drug combinations, but experimental screening approaches are costly and often identify only small numbers of synergistic combinations. The DREAM consortium launched an open challenge to foster the development of in silico methods to computationally rank 91 compound pairs, from the most synergistic to the most antagonistic, based on gene-expression profiles of human B cells treated with individual compounds at multiple time points and concentrations. Using scoring metrics based on experimental dose-response curves, we assessed 32 methods (31 community-generated approaches and SynGen), four of which performed significantly better than random guessing. We highlight similarities between the methods. Although the accuracy of predictions was not optimal, we find that computational prediction of compound-pair activity is possible, and that community challenges can be useful to advance the field of in silico compound-synergy prediction.